A scanning electron microscope (SEM) using an electron beam which is used to observe, inspect and measure a sample accelerates electrons emitted from an electron source and irradiates the electron so as to be converged on a surface of the sample using an electrostatic or electromagnetic lens. The electrons may be called as primary electrons. When the primary electron is incident, secondary electrons or reflection electrons may be generated from the sample. The secondary electrons or the reflection electrons are detected while scanning the electron beam so as to be deflected to obtain a minute pattern on the sample or a scanning image of composition distribution. Further, electrons which are absorbed onto the sample are detected to form an absorbed current image.
As a desirable function of the scanning electron microscope, there is a function of performing scanning with a wide viewing field without causing the significant lowering of a resolution of the electron beam. As the miniaturization of a semiconductor is progressed, a two-dimensional high speed inspection of a resist pattern is required and scanning with a wide viewing field is required in order to expand an inspection area and lower a shrinkage.
In order to achieve the above object, it is required to reduce a deflected chromatic aberration which is generated by the deflection of the electron beam. As an implementing method thereof, Patent Literature 1 and Patent Literature 2 suggest to use an electron optical element represented as E×B in which an electromagnetic deflector and an electrostatic deflector are combined. The E×B element is also used as a part of an energy filter of the electron beam or a deflecting element of the secondary electrons, which is disclosed in Patent Literature 3, Patent Literature 4, and Patent Literature 5 and Non-Patent Literature 1.